The scattering of DM on nuclei is dominated by DM scattering on single
nucleons. To leading order in the chiral expansion the scattering is
therefore described by the interactions of DM with nonrelativistic
nucleons and protons for which the EFT Lagrangian
is [1]}, [2]},
\({\cal L}_{\rm NR}=\sum _{i,N} c_i^N(q^2) {\cal O}_i^N\,,\) 
